Knead the mince with the rest of the ingredients and make meatballs the size of the muffin forms. Place the meatballs in the forms without smearing them with oil; they will release oil from the processed cheese and cheese.
Put the muffin tray in a preheated 392°F (200 °C) oven and bake for 15 min. until ready. Meanwhile, make the mashed potatoes as described on the packet.
Take the meatballs out of the tray carefully, so you don't rip them, and arrange in a suitable serving plate. Decorate by spraying the mashed potatoes on top like a hat.
Preparing the garnish:
In the still-warm muffin tray, place a large mushroom in each muffin holder. Then add finely diced ham on top, a little butter and grated cheese on top of it. Return to the oven and bake until ready.
Serve these next to the ready meatball muffins, along with a glass of cold beer.